JEE Advanced · 2021 · 03 Oct 2021 · Paper 1 · Electrostatics

Two point charges

- Q

and

+ Q / 3

are placed in the xy-plane at the origin (0,0) and a point (2,0), respectively, as shown in the figure. This results in an equipotential circle of radius

R

and potential

V = 0

in the xy-plane with its center at (b, 0). All lengths are measured in meters.

The value of

b

is ____ meter.

Answer: 3

Solution

From the previous calculation, the equipotential circle has equation

(x - 3)^{2} + y^{2} = 3

.

The center is at (3, 0), so b = 3 m.

JEE Advanced · 2021 · 03 Oct 2021 · Paper 1 · Numerical answer

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